package com.sys.app.web.controller;

import com.sys.app.entity.sys.myConstants;
import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.RequestMapping;


import javax.imageio.ImageIO;
import javax.servlet.http.HttpServletResponse;
import javax.servlet.http.HttpSession;
import java.awt.*;
import java.awt.image.BufferedImage;
import java.io.IOException;

import java.util.Random;

/**
 * 验证码
 */
@Controller
@RequestMapping("captcha")
public class CaptchaController {

    @GetMapping("/index.do")
    public void captchaPng(HttpServletResponse response, HttpSession session) throws IOException {
        int width = 63;
        int height = 34;
        Random random = new Random();
        response.setContentType("image/jpeg");
        response.setHeader("Pragma", "No-cache");
        response.setHeader("Cache-Control", "no-cache");
        response.setDateHeader("Expires", 0L);
        BufferedImage image = new BufferedImage(width, height, 1);
        Graphics g = image.getGraphics();
        g.setColor(this.getRandColor(200, 250));
        g.setFont(new Font("Times New Roman", 0, 28));
        g.fillRect(0, 0, width, height);


        for(int i = 0; i < 40; ++i) {
            g.setColor(this.getRandColor(130, 200));
            i = random.nextInt(width);
            int y = random.nextInt(height);
            int x1 = random.nextInt(12);
            int y1 = random.nextInt(12);
            g.drawLine(i, y, i + x1, y + y1);
        }

        String strCode = "";

        for(int i = 0; i < 4; ++i) {
            String rand = String.valueOf(random.nextInt(10));
            strCode = strCode + rand;
            g.setColor(new Color(20 + random.nextInt(110), 20 + random.nextInt(110), 20 + random.nextInt(110)));
            g.drawString(rand, 13 * i + 6, 28);
        }
        session.removeAttribute(myConstants.CAPTCHA_CODE_KEY);
        session.setAttribute(myConstants.CAPTCHA_CODE_KEY, strCode);
        g.dispose();
        ImageIO.write(image, "jpeg", response.getOutputStream());
        response.getOutputStream().flush();
    }





    private  Color getRandColor(int fc, int bc) {
        Random random = new Random();
        if (fc > 255) {
            fc = 255;
        }

        if (bc > 255) {
            bc = 255;
        }

        int r = fc + random.nextInt(bc - fc);
        int g = fc + random.nextInt(bc - fc);
        int b = fc + random.nextInt(bc - fc);
        return new Color(r, g, b);
    }





}
